화학공학소재연구정보센터
Journal of Molecular Catalysis A-Chemical, Vol.413, 100-106, 2016
Catalytic oxidation of 2,4,6-tribromophenol using iron(III) complexes with imidazole, pyrazole, triazine and pyridine ligands
Five types of non-heme iron complexes, coordinated with imidazole, pyrazole, triazine and pyridine ligands, which had been previously synthesized, were used in the following studies. Among these complexes, the mer-[FeCl3(terpy)] complex showed the highest catalytic activity for the oxidative degradation of 2,4,6-tribromophenol (TrBP) using KHSO5 as an oxygen donor. The turnover numbers for the degradation and debromination of TrBP in the mer-[FeCl3(terpy)]/KHSO5 catalytic system were estimated to be 1890 1 and 4020 216, respectively. The catalytic activity was significantly inhibited at pH 4-7 in the presence of a humic acid, a major component of landfill leachates. However, the percent of TrBP degradation and debromination increased at pH 8. GC/MS analyses showed that a major oxidation product was 2,6-dibromo-p-benoquinone (DBQ) and its level decreased with increasing reaction time, suggesting that organic acids (identified by LC/TOF-MS) are formed via the ring -cleavage of DBQ Mineralization to CO2 was observed to be 15% as a result of the oxidation for a 3 h period, where TOC values before and after the reaction were measured. Absorption spectra of mer-[FeCl3(terpy)] with m-chloroperoxybenzoic acids as an oxygen donor in acetonitrile showed that a center metal, Fe, formed a peroxide complex with the oxygen donor. (C) 2015 Elsevier B.V. All rights reserved.